Pump assembly



Feb. 11, 1964 w. H. HARNAGE 3,120,907

PUMP ASSEMBLY Filed Aug. 15, 1961 Z? I Z7 /3 INVENTOR ATTORNEYS United States Patent Ofifice 3,120,907 Patented Feb. 11, 1964 3,12%,907 PUMP ASSEMBLY William H. Harnage, Huntington Park, Califi, assignor to The Draekett Company, Cincinnati, Ohio, a corporation of ()hio Filed Aug. 15, 1961, Ser. No. 131,602 9 Claims. (Cl. 222321) This invention relates to improvements in dispensing devices of the type which comprise a pump barrel having a reciprocable plunger which requires to be angularly oriented with respect to the barrel. The present application is a continuation in part of my prior application, Serial No. 116,573, filed June 12, 1961, disclosing a pump of the type in question in which the desired orientation is secured by means of a key on the plunger coacting with a keyway on a collar fixedly applied on the end of the pump barrel. The arrangement is such that in assembling the pump, the plunger stem with the dispensing head removed is assembled with the collar and, after reception of the collar about the plunger stem and in operative relation with the key or keys thereon, the dispensing head is then applied to the upper end of the plunger stern. This, of course, requires orientation of the collar and the plunger relative to each other to bring the key and keyway into registry.

It is a primary object of the instant invention to facilitate the assembly of pumps of this type and, in particular, to facilitate not only the angular orientation of the respective parts as above mentioned, but also in a preferred form of the invention to facilitate initial entry of the plunger stem into the annular collar.

In order to achieve the aforesaid ends, the annular collar which defines a guide bore for sliding reception of the stem and is provided with one or more keyways for cooperation with a key or keys on the stem, is provided with an axially depending cam or cams having an inclined cam surface extending into the keyway to rotate the plunger stem to such position as will bring its key into the keyway incident to axial assembly of the plunger stem and collar.

In the preferred form of the invention a pair of diametrically opposed keys and keyways are provided to the end that the axial thrust resulting from assembly of parts may be equally distributed without tending tocant or axially misalign the parts. The assembly of the respective parts is further facilitated by providing the cam or cams of the collar with radially inner surfaces constituting an extension of the guide bore defined by the collar and in alignment therewith, and by providing the plunger stem with a pilot portion in advance of the key or keys thereon for free rotary reception in the said extension of the guide bore, whereby to maintain the parts axially aligned during their angular orientation as caused by coaction between the ends of the key or keys and the cam surface or surfaces with which they cooperate.

Further, in order to facilitate the initial insertion of the pilot portion into the guide bore or guide bore extension, the cam or cams are provided with inwardly inclined or generally conical guide surface or surfaces coaxial with or converging toward the guide bore for thus directing the pilot into said bore in the manner of a funnel.

Further incidental features and advantages of the invention will be apparent from the following detailed description in conjunction with the accompanying drawing in which:

FIGURE 1 is a view partially in side elevation and partially in section of a completely assembled pump structure in accordance with the invention, as operatively associated with a container cap in readiness for application to a fluid container.

FIGURE 2 is a somewhat enlarged detail section taken in a radial plane of the device shown in FIGURE 1 and showing the interconnections between the pump barrel, collar and plunger stern.

FIGURE 3 is a sectional view in the same plane as FIGURE 2 of the collar per se.

FIGURE 4 is a bottom plan view of the collar shown in FIGURE 3.

FIGURE 5 is a section on the line 5-5 of FIGURE 4 and showing in broken lines the plunger stem with its pilot portion inserted into the guide bore and the ends of the plunger stem keys in initial engagement with the cam surface.

Referring now in detail to the accompanying drawings, the pump structure shown in FIGURE 1 in its entirety comprises a pump structure shown in FIGURE 1 in its entirety comprises a pump barrel or cylinder 10, the interior of which defines a pump chamber. At its lower end the pump barrel is formed with a somewhat constricted portion 11 receiving the upper end of a suction tube 12 through which fluid is drawn upwardly from the container and into the pump barrel. The tube 12, as shown, is formed with a slight bend 12a so that its lower end 12b is offset to one side of the axis of the barrel 10 for disposition in a bottom corner of the fluid container to which the pump is applied, in order that when the container is tilted to cause the last remnants of its contents to flow into said corner, the pump will be properly positioned to remove it.

At its upper end 14 the pump barrel is open in an axial direction for reception of a reciprocating piston or plunger 15 which is normally projected upwardly by means of a compression spring 16 within the barrel, as best seen in FIGURE 2. The plunger 15 is of a diameter for snug reception in the barrel in accordance with usual practice and is provided with a relatively reduced diameter plunger stem 18 projecting upwardly and reciprocable through the upper end of the barrel. At its upper end the plunger stem carries a suitable dispensing head 19 having a discharge spout 20 which is directed radially in the same direction as the bent or offset lower end portion 12b of the suction tube, thus to be properly oriented with respect to the tube when the entire container and pump structure are tilted for dispensnig in the manner above described.

In accordance with well known practice, the pump is actuated by repeated finger pressure on the finger piece or portion 2 1.

Also, in accordance with well known practice, both the plunger stem 18 and the plunger 15 have axial openings therethrough in communication with the tube 12 and also with the discharge spout 20 and it will be understood that the pump structure is provided internally with usual valve means for causing unidirectional upward flow of fluid and discharge thereof through the spout 20 incident to reciprocation of the plunger 15.

Encircling the pump barrel 10 adjacent its upper end 14 is an outwardly projecting radial flange 23. Disposed around the upper end portion of the barrel and seated on this flange 23, there is shown a centrally apertured con tainer cap 25 adapted in any usual manner to support the pump on the container neck or spout in such manner that the lower portion of the barrel 10 and its associated tube 12 depend into the container. The annular collar 26 which is secured on the open end of the pump barrel also has a radially projecting flange 27 which overlies the cap 25 and coacts with the first flange 23 to axially confine the cap and conversely to secure the assembled pump structure against axial displacement with respect to the cap. The collar 26, in addition to its more or less incidental use in positioning the cap 25, serves various additional functions of importance to the present invention. In particular, it will be seen in FIGURE 2 that the inner periphery of the annular collar 26 defines a guide bore 28 forsliding reception of the stem. Moreover, the collar is formed with one or more keyways 30, which are illustrated in the preferred embodiment as comprising a pair of such keyways in diametrically opposed relation opening into the guide bore 28. The guide bore will normally bein wiping and guiding reception with the plunger stem 18 while the keyways 39 will slidably receive and cooperate with keys 32 formed on the plunger stem but, in the preferred embodiment, terminating somewhat short of the upper end of the stem whereby the upper end may define a free end or pilot 29 (FIGURE adapted for initial reception and rotary disposition in the guide bore and thereby providing a rotary connection between the stem and the annular collar, about which these parts may be relatively rotated to bring the keys and keyways 32 and 30 respectively into axial alignment. For automatically relatively rotating the collar 26 and plunger stem 18 to thus bring them into properly oriented relation, the collar is provided with at least one cam, and in the illustrated embodiment is shown with a pair of depending cams, eachdesignated 34, so arranged that the radially inner surface of each defines an extension of the guide bore 23 to thus initially receive and cooperate with the pilot 29 of the valve stem. The axially presented depending end of each cam 34 is formed as a generally helically inclined cammed surface 35 which, in the present instance, comprises two oppositely inclined portions, each leading into one of the keyways 30. The arrangement is such that in this embodiment each such'cam is provided with a lobe 36 medially between the keyways fail- 39. The cam surfaces 35 of each cam will be positioned to coact with the respective ends of the keys 32 in the event the same are axially misaligned with respect to the keyways 30 during assembly of the collar and plunger stem, and in such event will automatically rotate the parts to their properly oriented positions incident to relative axial mov ment between the parts toward their assembled positions. This will automatically occur at all times except in the rare instances in which the points of initial engagement between the ends of the keys 32 and the respective cams are centered with respect to the lobes 36, at which time only a slight amount of relative rotary movement in either direction need be imparted to the parts by external sources in order to move them from their dead-centered relationship and to cause them to coact automatically to orient themselves. a

In order to facilitate the initial insertion of the pilot 29 into the guide bore 23, the cam surfaces 35 of the cams 34 are formed to provide a generally conical guide surface or surfaces coaxial with and converging inwardly toward the guide bore 28. See FIGURES 3 and 5.

Thus in the assembling of the pump structure above described, the barrel 1t and tube 12 may, if desired, be pre-assembled in suitable manner and the compression spring 16 and such valve parts or other structure as may be required within the barrel or cylinder are inserted therein, following which the plunger and plunger stem 18, after having been duly assembled or integrally formed, are inserted into the open upper end 14 of the barrel. The discharge head 19 at this time is omitted from the stem. The container cap where employed, may be placed in operative position about the barrel and resting on the flange 23 at this time or may have been thus placed prior to the assembly steps previously mentioned. After the partshave been thus assembled with respect to the pump barrel 19, the collar 26 is then fitted over the stem 18. It will first receive the free or unkeyed upper end or pilot 29 of the plunger stem, which will be guided by the cam surfaces 35 into properly centered relation for reception in the guide bore 23 in advance of the keys 32-32. As the collar then moves axially onto the stem 18, its earns 34 will operatively engage the upwardly presented ends of the keys 32 so that normally continued axial assembly movement of these parts and the ensuing camming engagement between the cams 3 and keys 32 will automatically rotate or orient the respective parts to guide the keys into the keyways 39, following which the collar is moved downwardly for reception of the open upper end 14 of the barrel or cylinder 1%. When fully seated on this upper end the collar flange 27 will overlie the cap 25 to position it with respect to the pump assembly, and the various parts will be in operative relation for coaction in the manner earlier described. In such operation the cams 34, in addition to their function in facilitating the assembly of the respective parts, will continue to function as wiping and guiding elements for the plunger stem 13. In addition, it will be readily apparent that these cams 34 provide a convenient means for regulating the length of stroke of the plunger since they are disposed for engagement of their lobes with the plunger 15 to limit the upward stroke of the latter. It is obvious that the axial extent or dimension of the respective earns 34 may be varied as desired in different collars 26 whereby to provide a means for varying the length of the plunger stroke without change in any other part of the pump structure or its components. This is particularly desirable for use in a measuring pump or the like.

While the provision of a pair of cams and their associated keyways and keys is desirable as in the preferred embodiment, it will be obvious that the invention is neither restricted to this number of elements nor is it essential that more than a single such coacting set of cam, keyway and key be provided, nor is it essential that any given cam have a double slope as distinguished from a constant helical inclination toward a given keyway. In other words, although the present application discloses and specifically illustrates merely the preferred embodiment of the invention, this is subject to various modifications and alteration of details without departing from the scope of the invention as defined in the appended claims.

Having thus described my invention, I claim:

1. A pump assembly comprising a pump cylinder open at its upper end and encircled by a radial flange spaced from said end, a plunger disposed for reciprocation in said cylinder and having a hollow cylindrical plunger stem of smaller diameter than the interior of said cylinder reciprocable through said open end, and a discharge head fitted onto said plunger stem; a centrally apertured container cap having said open end of the cylinder dis posed through its aperture, the cap being seated against said flange, an annular collar secured on said open end of the cylinder and having a radially projecting flange overlying said cap and coacting with said first mentioned flange to axially confine said cap, said collar defining a guide bore for sliding reception of said stem and being formed with a pair of diametrically opposed keyways opening into said bore, said plunger stem having a pair of keys extending axially thereon for sliding reception in said keyways, said keys terminating short of the upper end of the plunger stem whereby said upper end of the plunger stern may be rotatably received in said bore to function as a pilot for the keyed portion of said stern; and axially depending cams on said collar disposed symmetrically on opposite sides of said keyways, each said cam having a lobe medially between said keyways and axially inclined cam surfaces extending from said lobe in opposite angular directions into the respective keyways, the diametrically opp'osed inner surfaces of the cams defining an extension of said guide bore for initial guiding reception of and rotary engagement with said upper end of the stem, the lobe portions of the cams also being axially inwardly inclined to guide said upper end into said bore extension, said lobe portions being in the path of reciprocation of said plunger to govern the length of its stroke.

V 2. A pump assembly comprising a pump cylinder open at its upper end and encircled by a radial flange spaced from said end, a plunger disposed for reciprocation in said cylinder and having a hollow cylindrical plunger stem of smaller diameter than the interior of said cylinder reciprocable through said open end, and having an upper end adapted for reception of a discharge head, a centrally apertured container cap having said open end of the cylinder disposed through its aperture, the cap being seated against said flange, an annular collar secured on said open end of the cylinder and having a radially projecting flange overlying said cap and coacting with said first mentioned flange to axially confine said cap, said collar defining a guide bore for sliding reception of said stem and being formed with a pair of diametrically opposed keyways opening into said bore, said plunger stem having a pair of keys extending axially thereon for sliding reception in said keyways, said keys terminating short of the upper end of the plunger stem whereby said upper end of the plunger stem may be rotatably received in said bore to function as a pilot for the keyed portion of said stem; and axially depending cams on said collar disposed symmetrically on opposite sides of said keyways, each said cam having a lobe medially between said keyways and axially inclined cam surfaces extending from said lobe in opposite angular directions into the respective keyways, the diametrically opposed inner surface of the cams defining an extension of said guide bore for initial guiding reception of and rotary engagement with said upper end of the stem, the lobe portions of the cams also being axially inwardly inclined to guide said upper end into said bore extension.

3. A pump assembly comprising a pump cylinder open at its upper end, a plunger disposed for reciprocation in said cylinder and having a hollow cylindrical plunger stem of smaller diameter than the interior of said cylinder reciprocable through said open end, an annular collar secured on said open end of the cylinder, said collar defining a guide bore for sliding reception of said stem and being formed with a pair of diametrically opposed keyways opening into said bore, said plunger stem having a pair of keys extending axially thereon for sliding reception in said keyways, and axially depending cams on said collar disposed symmetrically on opposite sides of said keyways, each said cam having a lobe medially between said keyways and axially inclined cam surfaces extending from said lobe in opposite angular directions into the respective keyways, the diametrically opposed inner surfaces of the cams defining an extension of said guide bore for initial guiding reception of the stem, the cams also being axially inwardly inclined to guide said upper end into said here extension.

4. A pump assembly comprising a pump cylinder open at its upper end, a plunger disposed for reciprocation in said cylinder and having a hollow cylindrical plunger stem of smaller diameter than the interior of said cylinder reciprocable through said open end, an annular collar secured on said open end of the cylinder, said collar defining a guide bore for sliding reception of said stem and being formed with a pair of diametrically opposed keyways opening into said bore, said plunger stem having a pair of keys extending axially thereon for sliding reception in said keyways, said keys terminating short of the upper end of the plunger stem whereby said upper end of the plunger stem may be rotatably received in said bore to function as a pilot for the keyed portion of said stem; and axially depending cams on said collar, each said cam having an axially inclined cam surface, said surfaces extending in the same angular direction into the respective keyways, the diametrically opposed inner surfaces of the cams defining an extension of said guide bore for initial guiding reception of and rotary engagement with said upper end of the stem.

5. The combination defined in claim 4 in which the cams also are axially inwardly inclined to guide said upper end into said bore extension.

6. The combination defined in claim 5 in which said cams depend into the path of reciprocation of said plunger to govern the length of its stroke.

'7. A pump assembly comprising a pump cylinder open at its upper end, a plunger disposed for reciprocation in said cylinder and having a hollow cylindrical plunger stem reciprocable through said open end, an annular collar secured on said open end of the cylinder, said collar defining a guide bore for sliding reception of said stem and being formed with a keyway opening into said bore, said plunger stern having a key extending axially thereon tor sliding reception in said keyway, said key terminating short of the upper end of the plunger stem whereby said upper end of the plunger stem may be rotatably received in said bore to function as a pilot for the keyed portion of said stem; and an axially depending cam on said collar extending into said pump cylinder, said cam having a generally helically inclined cam surface extending from substantially its lowermost extremity into the said keyway, said cam having a cylindrically curved inner wall defining an extension of said guide bore for initial guiding reception of and rotary engagement with said upper end of the stem.

8. A pump assembly comprising a pump cylinder open at its upper end, a plunger disposed for reciprocation in said cylinder and having a cylindrical plunger stem of smaller diameter than the interior of said cylinder reciprocable through said open end, an annular collar secured on said open end of the cylinder, said collar defining a guide bore for sliding reception of said stem and being formed with a keyway opening into said bore, said plunger stem having a key extending axially thereon for axial sliding reception in said keyway, a pilot portion of circular cross section on the upper end of said plunger stem to be rotatably received in said bore, and an axially depending cam on said collar, having a helically inclined cam surface for rotatably orienting said key with respect to said keyway incident to relative movement of the collar onto said pilot portion and means carried by said assembly defining an extension of said guide bore for initial guiding reception and rotary engagement with said pilot portion.

9. A pump assembly as defined in claim 8 in which said means defining an extension of the guide bore is formed with a generally conical guide surface coaxial with and converging toward said guide bore for directing the said pilot into said bore.

References Cited in the file of this patent UNITED STATES PATENTS 2,094,423 Bernhardt Sept. 28, 1937 

1. A PUMP ASSEMBLY COMPRISING A PUMP CYLINDER OPEN AT ITS UPPER END AND ENCIRCLED BY A RADIAL FLANGE SPACED FROM SAID END, A PLUNGER DISPOSED FOR RECIPROCATION IN SAID CYLINDER AND HAVING A HOLLOW CYLINDRICAL PLUNGER STEM OF SMALLER DIAMETER THAN THE INTERIOR OF SAID CYLINDER RECIPROCABLE THROUGH SAID OPEN END, AND A DISCHARGE HEAD FITTED ONTO SAID PLUNGER STEM; A CENTRALLY APERTURED CONTAINER CAP HAVING SAID OPEN END OF THE CYLINDER DISPOSED THROUGH ITS APERTURE, THE CAP BEING SEATED AGAINST SAID FLANGE, AN ANNULAR COLLAR SECURED ON SAID OPEN END OF THE CYLINDER AND HAVING A RADIALLY PROJECTING FLANGE OVERLYING SAID CAP AND COACTING WITH SAID FIRST MENTIONED FLANGE TO AXIALLY CONFINE SAID CAP, SAID COLLAR DEFINING A GUIDE BORE FOR SLIDING RECEPTION OF SAID STEM AND BEING FORMED WITH A PAIR OF DIAMETRICALLY OPPOSED KEYWAYS OPENING INTO SAID BORE, SAID PLUNGER STEM HAVING A PAIR OF KEYS EXTENDING AXIALLY THEREON FOR SLIDING RECEPTION IN SAID KEYWAYS, SAID KEYS TERMINATING SHORT OF THE UPPER END OF THE PLUNGER STEM WHEREBY SAID UPPER END OF THE PLUNGER STEM MAY BE ROTATABLY RECEIVED IN SAID BORE TO FUNCTION AS A PILOT FOR THE KEYED PORTION OF SAID STEM; AND AXIALLY DEPENDING CAMS ON SAID COLLAR DISPOSED SYMMETRICALLY ON OPPOSITE SIDES OF SAID KEYWAYS, EACH SAID CAM HAVING A LOBE MEDIALLY BETWEEN SAID KEYWAYS AND AXIALLY INCLINED CAM SURFACES EXTENDING FROM SAID LOBE IN OPPOSITE ANGULAR DIRECTIONS INTO THE RESPECTIVE KEYWAYS, THE DIAMETRICALLY OPPOSED INNER SURFACES OF THE CAMS DEFINING AN EXTENSION OF SAID GUIDE BORE FOR INITIAL GUIDING RECEPTION OF AND ROTARY ENGAGEMENT WITH SAID UPPER END OF THE STEM, THE LOBE PORTIONS OF THE CAMS ALSO BEING AXIALLY INWARDLY INCLINED TO GUIDE SAID UPPER END INTO SAID BORE EXTENSION, SAID LOBE PORTIONS BEING IN THE PATH OF RECIPROCATION OF SAID PLUNGER TO GOVERN THE LENGTH OF ITS STROKE. 